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    <doi>https://doi.org/10.1088/1742-6596/982/1/012008</doi>
    <renateDoi>https://doi.org/10.34657/17664</renateDoi>
    <title>Parametric computational study of sheaths in multicomponent Ar/O2 plasma</title>
  </source>
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      <sentence id="s1" text="Parametric computational study of sheaths in multicomponent Ar/O2 plasma Our study is devoted to sheath structures emerging in Ar/O2 plasma .">
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          <entity id="e1" type="G#PlasmaSource" text="ar o2" start="7" end="8" orig_id="0"/>
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      <sentence id="s2" text="By means of two dimensional PIC/MCC computer model two configurations were investigated-sheath structure in the vicinity of a cylindrical Langmuir probe for two different biases and changes of the sheath structure when a cylindrical probe passes into a semi-planar probe .">
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      <sentence id="s3" text="It was shown that O+ ions play important role in shielding out negative bias of a solid immersed in Ar/O2 plasma and edge effects of a semi-planar probe on its sheath structure were evaluated .">
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      <sentence id="s4" text="Plasma that contains more species of both negative and positive ions [1][2][3], so called multicomponent plasma, is widely used in many industrial applications nowadays, particularly in plasma-assisted technologies (i .">
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          <entity id="e14" type="G#PlasmaApplication" text="plasma assisted technologies" start="26" end="28" orig_id="12"/>
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      <sentence id="s5" text="thin film deposition, plasma etching, etc.) .">
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          <entity id="e16" type="G#PlasmaApplication" text="thin film deposition plasma etching" start="0" end="5" orig_id="14"/>
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      <sentence id="s6" text="Multicomponent plasma is often a mixture of reactive gases that is chemically active and composed of mutually interacting charged and neutral particles that are out of the thermodynamic equilibrium .">
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          <entity id="e21" type="G#PlasmaMedium" text="mixture of reactive gases" start="5" end="9" orig_id="19"/>
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      <sentence id="s7" text="Thus, it is very demanding to describe it theoretically and therefore it is often taken advantage of computer modelling approach in multicomponent plasma research [4,5] .">
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          <entity id="e28" type="G#Species" text="ar o 2" start="19" end="21" orig_id="26"/>
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      <sentence id="s9" text="The results were obtained by 2D PIC/MCC computer model, which is described in Section 2 .">
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      <sentence id="s11" text="Further, results of a parametric study that captures a transition from a cylindrical to a planar solid substrate are also presented here .">
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      <sentence id="s12" text="The sheath structures in the present contribution were modelled by means of two-dimensional PIC/MCC computer model that was already used to explore sheath structures in purely electronegative plasma [6] .">
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      <sentence id="s13" text="The results of the chemical kinetics model published in [7] were adopted and used as an input for our simulation .">
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      <sentence id="s14" text="The kinetic model takes into account more than 100 reactions between neutral, charged and excited species in Ar/O 2 plasma that are described by rate constants and consequently, continuity equations for all species in the ensemble are solved to obtain their number densities .">
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      <sentence id="s15" text="Only the most important charged particles were considered in the PIC simulation: e − , O − , Ar + , O + , O 2 + .">
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      <sentence id="s17" text="First of all, the sheath around a single cylindrical Langmuir probe with 2×10 −4 m radius was investigated .">
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      <sentence id="s19" text="(The term simplified electronegative plasma means in our context argon plasma in which O − ions are also present; therefore e − , Ar + and O − ions represent the only charged particles in this first approximation of Ar/O 2 plasma .">
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      <sentence id="s20" text="The amount of O − ions is given by the electronegativity α which is defined as: α = n O− / (n e− + n O− ), where n O− denotes number density of O − ions and n e− that of electrons.) Significant differences are observed for −10 V bias of the probe .">
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    <keywords>
      <keyword>semi planar probe</keyword>
      <keyword>plasma assisted technologies</keyword>
      <keyword>pic mcc computer model</keyword>
      <keyword>shielding out negative bias</keyword>
      <keyword>simplified electronegative plasma</keyword>
      <keyword>chemical kinetics model</keyword>
      <keyword>computer modelling approach</keyword>
      <keyword>multicomponent plasma research</keyword>
      <keyword>electric field intensity</keyword>
      <keyword>thin film deposition</keyword>
      <keyword>Low Temperature Plasma Research</keyword>
    </keywords>
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